Riveted structure



Dect. 30, 1930. V 1 E, KALGREN 1,787,076

RIVETED STRUCTURE Origiral Filed March 12. 1927 JP/lie Patented Dec. 3), 1930 JOHN n. KALeRniv, or ininnnnroiiis, MINNESOTA, .essieivonro J. it. cin-.emrooisi-l Lram?, or Miiviviinroiiis, iviiizrniisofra,iL Aooaronafrioiv `orfiaiivirriuso'rii ,I

aivnrnn STRUCTURE Original application filed March 12, 1927, Serial No. 174,995'. `liividei and thisapplication filed January ze, i930. seriai ivo. 424,028.

My present invention relates to a riveted Y A .the members of vwhich are tobe .riveted 1n structure and is a divisionv of my co-pending application entitled Riveted structure and machine for producing the same, liled March 12,1927 under Serial Number 1'? L1,995.

Heretofore it has been the general practice in connecting two members of a riveted struc ture, one of which is made oit wood or other compressible material, toV insert a rivet through aligned bores in said members, apply a washer thereto and upset theend of the rivet against the washer to torni a head thereon. ln suoli a structure in case. the wooden member shrinks the rivet will become loose so that said members are not rigidly connected and the wooden member is Iliable to split through the bore therein for the rivet.

My invention provides an extremely simple and highly eiiicient method in which the cus-V tomary washer is dispensed with, of forming a mushroom head on a rivet and clinching the same directly into the wooden member. This mushroom head is formed by setting up a whirling action on the end of the rivet, while held in the wooden member, with sufiicient'pressure to upset the rivet and simultaneously turn the peripheralv edge' of the mushroom head thus formed rearwardly and inwardly into the wooden member. During the formation of the mushroom head the wooden member is co.mpressed` to such a degree that in case said member shrinks the the'mushroom head directly into the wooden member prevents said member from splitting through that portion thereof clinched by the mushroom head.` n y This method of 'forming a mushroom' head directly against a compressible member and olinching the samethereto, not onlyv greatly strengthens the rivetedstiucture but reduces thev cost of construction by the saving of material and labor.

To the above end, generally stated, the invention consists of the"` novel method hereinafter described anddei'ined in the claims.

In the accompanying drawings, which illustrate the invention, like characters indi"- cate like parts throughout the several views.

Referring t-o the drawings:

rlihe clinching of Fig. y1l is fragmentary view of a structure,

the'apertured ear and through a bore' in the step 3 with its head 7 lbearing against said ear and with its end portion projecting outward or" the step 3i" Y v 'i VThe end of the rivet 6 is upsetagainstthe step 3 by a'rivetin'g inachi'neldisclosed and broadly claimed in the applicationheretofore identified. Forthe purpose ofthis case it is not thought necessary to illustrate this head 9. The abutment 8 is provided with a lconcave seat 10 4tor the rivet 'head y7 which The spinner headl9lis securedto the outer end of a revolublespindle 11 driven from any electric motor, not shown. Said spinner head 9 is biturcated and a spinner wheel 12, having a grooved periphery and comprisin two axially spaced sections, is loosely journaled onv a 'stud 13 mounted in the prongs of said liead. V The sections of the Vspinner wheel 12 This Y `machineexcept its abutment 8 andV spinner' are held in rearwardly diverging relation,

from their-"rivet-upsetting position, bythe prongs of the spinner head 9 and a wedgelike spacer 14 on said head.. 1 lt will be noted that the axial holes in the sections of the spinner head 9 flare inwardly and away from the stud 13 to permit said sections to rotate on the stud 13 with a y slight wobble movement .to compensate for their voblique relation tothe axis of said stud.

As the rivet 6 is aXially fed to the spinner Y wheel 12 the sections of said wheel engage the pend of the rivet 6 at diametrically opposite 5 points,. and hence, by theirl contact therewith arel rotatedinl reverse directions.'v This Contact of the spinner wheel 12 with the end o Yof the rivet 6iand the feeding of the` rivet Y 6a'xially thereto*remisev mushroomliead 15V p10 thereon. directly against theV step 3'. Simul taneously with the ormationof the .mush-` room head l5 the peripheral edge thereof is turned rearward .and inward into the stepl 3 l and thus elinehing the same directly into 1'5 the wood thereof.A

`During the formation of the mushroom head 15 ,thelmushrooml head 7 is pressed against. the step 3, whiehis held by the ear 5 and the. rivet 6 by the abutment 8', with n such force that said step is compressed Y around the rivet 6 and to sucha degree, that in case said step shrinks, it willfnotloosen Vsaidrivet; Y What I claim is: y Y

25 1. A methodof forming a mushroom head on a rivet andclinching the samev directly into a compressible member while support-L ing the rivet in said member, which consists in upsetting the end of the rivet byspinning 30l action directly against the member and simultaneously curling the peripheral edge of the V.head being formed rearwardly and inwardly toward .the rivet shank into the compressible material of said member, the curling edge '35 cuttingv and imbedding itself into' such 1na.-

terial on an inwardly directed are;

2. The method'of forming a' head on rivet and' lelinching the same simultaneously into a compressible member while supporting 40 therivet in said member, which consists in upsetting the end ofthe rivet by spinning action and curling the peripheral edge rearwardly cutting through the libres of .the come Y pressible material of lsaid member on airin- 4 5 wardly directed are,` whereby to' interlock therewith, and to Compress such:V material under the body of the .rivethad f In testimony whereof I altixmyy signature.

JOI-IN; KALGREN; 

